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Many parts of Musa balbisiana have been used widely in traditional medicine, food, or cosmetic purposes. The present study is aimed at obtaining the extract-enriching bioactive compounds from M. balbisiana and determining the bioactive activities of the extract. Total polyphenols and saponins in the extracts were quantified. The response surface method (RSM) was used to optimize the extraction with methanol support. The optimal extraction conditions were at 120 min in 65°C at the material/solvent ratio of 1/36 ( w / v ). The obtained extract containing 51.72 mg/gGAE of total polyphenols (TPC) and 41.66 mg/g of saponins (TSC) was evaluated for antioxidant, antibacterial, antifungal, and antidiabetic abilities. The extract of M. balbinasia fruit exhibited strong antioxidant activity. The IC50 112.57 μg/mL (DPPH) and 14.49 μg/mL (ABTS). The absorbance of the extract was 1.653 ± 0.030 at 250 ppm (RP assay). The antibacterial and antifungal inhibition exhibited a correlation with TPC and TSC. The extract inhibited Gram (+) S. aureus better than Gram (-) E. coli, while the inhibition percentage (I%) against A. flavus reached over 70% at 800 ppm. The IC50 value of the extract for anti-inflammatory activity was 187.91 μg/mL. The antidiabetic assessment revealed that methanolic extract showed quite strong inhibition with α-amylase (IC50 68.26 μg/mL) and α-glucosidase (IC50 72.61 μg/mL). The results of the study showed that M. balbinasia fruit is a potential source of bioactive phytochemicals, which can be used as a plant-based antioxidant, antibacterial, antifungal, anti-flammatorial, and antidiabetic agent. This is valuable information to support further studies to exploit and apply it in functional food, pharmaceutical, and cosmetic industries.

We evaluated methods aimed at improving the performance of full-cell including: i) Presodiating HC by discharging to 0.1 V in half-cell; ii) Presodiating HC by contacting with Na metal; iii) Activating by low current charging at a rate of C/20 initially, iv) Constant current charging to a cutoff voltage of 3.95 V then hold the voltage for 6 hours. The results showed that the cell being charged by low current density did not exhibit feasible work while the cell (iv) displayed an improvement in capacity while the cell (i) and the cell (ii) both are better in terms of Coulombic efficiency.

In this article, we propose a built-in ring differential transmission line for four-level pulse amplitude modulation (PAM4) signal integrity optimization. An optimized ring structure, which comes from the simplistic idea to leverage the voltage produced by near-end crosstalk inside the ring, is attached at the end of the transmission line to improve the eye diagram. Additionally, we introduce the comprehensive design guideline with analytically derived formulas that is beneficial to designers to obtain an accurate design without significant effort. The proposed structure is implemented on a 100 mm transmission line, six-layer printed circuit board. The proposed structure can achieve an improvement of up to 32.9% eye height with a 4 Gsps PAM4 signal.

Motivated by a call for risk discourse research in non-Western settings, this study examines how Vietnamese road safety video advertisements are constructed and interpreted. Following a literature review of risk and gender, the study first sets out socio-semiotic multimodal analysis of video advertisements to detail how concepts of risk and gender are constructed. Afterwards, I take an ethnographic-based approach in a series of interviews with professional Vietnamese women to gain insights into these concepts. Findings of the study reveal the expected female roles as wives and mothers in Vietnamese advertising as interpreted by Vietnamese women. The study contributes to an understanding of risk in this Asian setting and opens up the potential for a critical, interpretive approach to risk discourses that are grounded in lived experiences.

The discourses of risk serve to organise the ways in which we understand and respond to potential harms and threats, which have become a major concern in our daily life. However, the discourses of risk have not been extensively investigated using linguistic text-based methods on the multimodal level, nor deeply examined beyond Western contexts. Grounded in the literature of risk and multimodal discourse, the aim of the study is to demonstrate Multimodal Discourse Analysis from a Systemic Functional Linguistics perspective as a potential methodology to investigate how risk discourses are constructed in and through semiotic resources in a non-Western setting. Through a case study of child helmet awareness advertisements in Vietnam, the multimodal analysis reveals a comprehensive picture of risk discourses constructed across various semiotic modes. In this analysis, the discourses of risk are constructed through a negotiation of expert knowledge and traditional values to encourage the audience to take actions and provide helmets for their children. Findings of the study demonstrate the use of Systemic Functional multimodal approach to media and communication to provide evidence for risk discourses in the Vietnamese setting, which are at odds with the current literature and can potentially be extended to other contexts.

The article considers the problem of point control of the differential-difference equation with distributed parameters on the graph in the class of summable functions. The differential- difference system is closely related to the evolutionary differential system and moreover the properties of the differential system are preserved. This connection is established by the universal method of semi-discretization in a time variable for a differential system, which provides an effective tool in order to find conditions for unique solvability and continuity on the initial data for the differential-difference system. For this differential-difference system, a special case of the optimal control problem is studied: the problem of point control action on the controlled differential-difference system is considered by the control, concentrated at all internal nodes of the graph. At the same time, the restrictive set of permissible controls is set by the means of conditions depending on the nature of the applied tasks. In this case, the controls are concentrated at the end points of the edges adjacent to each inner node of the graph. This is a characteristic feature of the study presented, quite often used in practice when building a mechanism for managing the processes of transportation of different kinds of masses over network media. The study essentially uses the conjugate state of the system and the conjugate system for a differential-difference system — obtained ratios that determine optimal point control. The obtained results underlie the analysis of optimal control problems for differential systems with distributed parameters on the graph, which have interesting analogies with multi-phase problems of multidimensional hydrodynamics.

In this work, nano silver catalyst loaded on vanadium phosphorus oxide (Ag/VPO) for oxidation of styrene to benzaldehyde was synthesized by impregnating method including impregnating of VPO substrate with colloid solution of nano silvers. VPO substrate was prepared by microwave-assisted reaction of vanadium and phosphorus precursors. Meanwhile, nano Ag/PVP was prepared in solution using NaBH4 as reducing agent and polyvinylpyrrolidone (PVP) as protecting agent and spherical-shaped nano particles with mean diameter of about 7.5 nm determined by transmission electron microscopy (TEM) was obtained.

Sodium ternary layered oxides, typically NaNi1/3Mn1/3Co1/3O2 (NMC), are layered structures analogous to LiNi1/3Mn1/3Co1/3O2, and have been utilized extensively in sodium-ion batteries (SIBs). The cathode material was successfully synthesized by a sol-gel process followed by a calcination step at 900 °C for 12 h. The triple-phase integration denoted as P2, O1 and O3 in the NMC sample was evidently revealed on XRD diagrams. The composite cathode material acted as an O3 purity phase that exhibited relatively good performance that delivered an initial capacity of 140 mAh g−1 and sustained reversible capacities of nearly 110 mAh g−1 after 100 cycles. The kinetics of sodium intercalation of sol-gel NMC upon reversible Na+ insertion/de-insertion was evaluated via galvanostatic intermittence titration technique (GITT) and electrochemical impedance spectroscopy (EIS). The diffusion coefficients of Na+ deduced from the GITT curve were found to lie within a wide range, 10−9–10−12 cm2 s−1 for the charge process and 10−13–10−17 cm2 s−1 for the discharge process. This implies that the kinetics of Na+ extraction out of the NaxNi1/3Mn1/3Co1/3O2 host could be much more favored than Na+ insertion. Additionally, the evolution of diffusion coefficient and charge transfer resistance are consistent with the complex phase transition generally observed in sodium layered oxides.

With the new developments of natural language processing, increasing attention has been given to the task of Named Entity Recognition (NER). However, the vast majority of work focus on a small number of large-scale annotated datasets with a limited number of entities such as person, location and organization. While other datasets have been introduced with domain-specific entities, the smaller size of these largely limits the applicability of state-of-the-art deep models. Even if there are promising new approaches for performing zero-shot learning (ZSL), they are not designed for a cross-domain settings. We propose Cross Domain Zero Shot Named Entity Recognition with Knowledge Graph (DOZEN), which learns the relations between entities across different domains from an existing ontology of external knowledge and a set of analogies linking entities and domains. Experiments performed on both large scale and domain-specific datasets indicate that DOZEN is the most suitable option to extracts unseen entities in a target dataset from a different domain.

Abstract In this research, natural anthracite coal (ATC) originated from Vang Danh - Quang Ninh province in Viet Nam was firstly chemically purified and then calcined in inert gas (Ar) at 800 oC for different periods (t = 2, 3 and 6 h) to remove all the impurities and enrich the carbon content. The purity and graphitized structure of treated coal proved significantly while evaluating its structural parameters (the lateral crystallite size - La, stacking crystallite height - Lc, the average number of layers per carbon crystallite - Naverage, and the average number of carbon atoms per aromatic lamellae - n)1, 2 and morphology. After purification step, ATC possesses relatively high carbon content (96.0%) and its impurities were mostly removed. The structure of heat-treated ATC samples is like hard carbon. Besides, its graphene interlayer spacing is larger than that of graphite. These features seem to be potential for application of ATC as negative electrode materials for both Li and Na rechargeable batteries. In batteries testing, using ATC calcined at 800 oC for 3 hours as anode material in lithium half-cell exhibited a quite good specific capacity (170.1 mAh g-1), which is much higher than the value obtained for commercial hard carbon (162.2 mAh g-1). Moreover, Coulombic efficiency of ATC is almost absolute (99.8%). In sodium half-cell, the sample calcined at 800 oC for 2 hours gave much smaller specific capacity of 130.5 mAh g-1 than hard carbon one (280 mAh g-1). Nevertheless, Coulombic efficiency of ATC anode in lithium half-cell and sodium half-cell throughout 100 cycles remained absolutely at 99.6%, while their values for hard carbon anode were 99.9% and 99.7%, respectively. References Abou-Rjeily, J.; Laziz, N. A.; Autret-Lambert, C.; Outzourhit, A.; Sougrati, M.-T.; Ghamouss, F., Towards valorizing natural coals in sodium-ion batteries: impact of coal rank on energy storage. Scientific Reports 2020, 10 (1), 1-10. Manoj, B.; Kunjomana, A., Study of stacking structure of amorphous carbon by X-ray diffraction technique. Int. J. Electrochem. Sci 2012, 7 (4), 3127-34. Acknowledgement This work is supported by Viet Nam National University Ho Chi Minh City (VNUHCM) under grant number B2020-18-06

Compute Unified Device Architecture (CUDA), a parallel computing platform and programming model architecture developed by NVIDIA, has grown to become the defacto standard for using Graphic Computing Units (GPUs) to solve the problem of High-Performance Computing (HPC) at the moment. This paper presents a benchmarking to show CUDA and GPU's advantage in accelerating computing performance in image processing. We take the Exemplar-based inpainting algorithm of Criminisi et al. to be the case study for the research. This paper optimizes the Exemplar-based inpainting algorithm (EBII) using GPU instead of CPU like other implementations before. We justify that the GPU can improve the performance of the algorithm to state-of-the-art level. We compare the algorithm's velocity between multiple implementations: one public Matlab implementation, one public C++ implementation, and our version using GPUs.

The herbicide compounds contain aromatic ring and chlorine atom such as 2,4-dichlorophenoxylacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic (2,4,5-T) cause serious environmental pollution. However, it is very difficult to decompose by chemical, physical and biological methods. The high voltage direct current electrochemical method can be control to form plasma on metallic electrodes. Thus, it creates active species like as H 2 , O 2 , H 2 O 2 and free radicals such as: H•, O•, OH•. Especially, OH• free radicals that has a high oxidation potential, so it is possible to oxidize benzene oring compounds more effective. The iron electrode is used in the studing to combine the dissolve process of the iron anode electrode with aims is to create Fe 2+ ions and electrochemical fenton reaction. Besides, the flocculation process by Fe(OH) 2 also happen. The plasma will appear with a voltage of 5 kV on the iron electrode in a solution of 30 mg/L 2,4-D or 2,4,5 T. After a period time of the reaction, the aromatic oring compounds contaning the chlorine was treated, the electric conductivity of the solution increases due to the amount of Cl - ions releasing in the solution. The degradable products of the 2,4-D and 2,4,5-T were analyzed qualitatively by the gas chromatograph mass spectrometer GC-MS 6890-5975 Agilent system. The results described that the straight chain carboxylic acids were formed in the solution. These compounds are easy to oxidize thoroughly under appropriate conditions in solution by OH• free radicals . Moreover, the 2,4-D and 2,4,5-T were also analyzed quantitatively by a calibration curve from GC-MS 6890-5975 Agilent system or high performance liquid chromatograph HPLC 1100 Agilent system. The treatmental process can be controlled to achieve optimum performance by technological factors such as input voltage, distance between anode and cathode electrodes, initial concentration of 2,4-D and 2,4,5-T as well as flowing air through solution. The analysis results showed that the degradation efficiency of 2.4-D and 2,4,5-T reached at 99.98%; 99.83%, respectively.

This research aims to evaluate the influence of different 3D metals (Fe, Co, and Ni) substituted to Mn on the electrochemical performance of P2-NaxMe1/3Mn2/3O2 material, which was synthesized by the coprecipitation process followed by calcination at high temperature. X-ray diffraction (XRD) results revealed that the synthesized Mn-rich materials possessed a P2-type structure with a negligible amount of oxide impurities. The materials possessed their typical cyclic voltammogram and charge-discharge profiles; indeed, a high reversible redox reaction was obtained by NaxCo1/3Mn2/3O2 sample. Both NaxCo1/3Mn2/3O2 and NaxFe1/3Mn2/3O2 provided a high specific capacity of above 140 mAh·g−1; however, the former showed better cycling performance with 83% capacity retention after 50 cycles at C/10 and high rate capability. Meanwhile, the Ni-sub NaxNi1/3Mn2/3O2 exhibited excellent cycling stability but a low specific capacity of 110 mAh·g−1 and inferior rate capability. The diffusion coefficient of Na+ ions into the structure tended to decrease with a depth of discharge; those values were in the range of 10−10–10−9 cm2·s−1 and 10−11–10−10 cm2·s−1 in the solid solution region and biphasic region, respectively.

In this paper, we propose a design methodology for multiple bus structures implemented on flexible printed circuit board (FPCB) with mesh ground structure. The proposed methodology suggested an optimum distance of the signal lines and relative location with respect to the grid to guarantee the $50\Omega$ characteristic impedance without resonance in insertion loss and with minimum crosstalk. Also, the proposed design shows identical impedance of signal lines in time-domain-reflectometer (TDR) measurements and improves Far-End Crosstalk (FEXT) by 4.3 dB in and Near-End Crosstalk (NEXT) 6.1 dB with respect to conventional design (signal lines with $50\Omega$ characteristic impedance at grid center) at 1.25 GHz for the design targeted to be used at C-PHY with 20-mm multiple bus structures in 2-layer FPCB using polyimide.

In this work, InAlN/GaN metal–insulator–semiconductor high-electron-mobility transistors (MIS-HEMTs) based on the AlN/GaN superlattice channel have been demonstrated. The devices fabricated with the AlN/GaN superlattice channel perform superior characteristics over other relative devices consisted of the conventional single GaN channel. The effective channel-electron mobility, maximum drain current, ON-resistance, and the ION/IOFF ratio of the superlattice-channel-based MIS-HEMTs are approximately 932 cm2 V−1 s−1, 57 mA/mm, 62 Ω mm, and 108 and those of the conventional structure are 820 cm2 V−1 s−1, 48 mA/mm, 92 Ω mm, and 104, respectively. Additionally, this work has shown that the AlN/GaN superlattice channel has the ability to suppress leakage currents. As a result, the breakdown voltage of the device based on the superlattice structure without the back barrier is approximately 500 V, which is 430 V higher than that based on the single GaN channel.

Introduction: Localized high concentration electrolytes (LHCE) have been intensively studied due to their unique properties, especially in suppressing the Na dendrite formation and long-term cycling. Therefore, the low electrochemical performance of the P2-type cathode can be overcome by using LHCE. Methods: P2-type sodium layered oxides Na2=3Mn2=3M1=3O2 (M = Fe, Co, Ni) cathode materials were synthesized via a simple co-precipitation following a supported solid-state reaction. XRD and Rietveld method analyzed the phase composition and lattice parameters. SEM images observed the morphology of materials. The half-cell of three cathode were performed in LHCE consisting of 2.1 M sodium bis(fluorosulfonyl)imide (NaFSI) dissolved in 1,2-dimethoxyethane (DME) and bis(2,2,2-trifluoroethyl) ether (BTFE) (solvent molar ratio 1:2). The galvanostatic charge-discharge, striping-plating, and linear sweep voltage tests were carried out to investigate the electrochemical behaviors. Results: As-prepared electrode materials exhibited discharge capacities of 94.5, 147.1, and 142.9 mAh/g at C/10 in the potential range of 1.5-4.2 V for Na2=3Mn2=3Fe1=3O2 (MFO), Na2=3Mn2=3Co1=3O2 (MCO) and Na2=3Mn2=3Ni1=3O2 (MNO), respectively. Interestingly, the MNO cathode material has a superior cycling performance with 86.5% capacity retention after 100 cycles than MCO and MFO. Conclusion: Such superior electrochemical performance of synthesized MNO could be ascribed to the combined synergistic effects between the nickel partially substituted MNO cathode structure and using LHCE 2.1 M NaFSI/DME-BTFE (1:2). Nickel substituted MNO cathode exhibited the enhancement of discharge capacity and the long cycling stability in LHCE due to the mitigation of dendrite formation on sodium metal anode.

In this work, a single phase of P2-Na0:67Mn0:75Ni0:25O2 (NaMNO) material was successfully synthesized via a coprecipitation method with the size varying from 2 to 4 mm. According to the atomic absorption spectroscopy (AAS), all the metallic elements were uniformly distributed in the bulk material with the desired ratio Mn¸Ni = 3¸1. The electrochemical properties of P2-NaNMO were investigated in carbonate-based electrolytes using 1M NaClO4 or 1M NaPF6. Among these electrolytes, this cathode exhibited the best electrochemical performance with initial capacity up to 205.7 mAh/g and capacity retention reaches 63.2% during 60 cycles when using 1M NaClO4/PC + 2% (v/v) VC. Indeed, vinylene carbonate (VC) additive plays an important role in improving the performance of NaMNO cathode through the formation of a stable cathode electrolyte interphase layer (CEI). Electrochemical impedance spectroscopy (EIS) was performed to demonstrate CEI layer formation indicated by the elevation of the electrode surface film and double layer impedance in the initial cycle. During cycling, galvanostatic intermittent titration technique (GITT) helps to calculate the Na+ ion diffusion coefficient, which was increased clearly at the working voltages of Mn3+/Mn4+ and Ni3+/Ni4+ redox couples.

Introduction: Ionic liquids (ILs) have become a prospective candidate to replace the conventional electrolytes based on the volatile organic-solvents in lithium-ion batteries. However, the drawbacks of high viscosity and low ionic conductivity have restricted the high rate capacity and energy density in practical batteries. With the aims to resolve these problems and design a safe electrolytes with high electrochemical stability, mixtures of ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl) imide (EMITFSI) with different amounts of ethylene carbonate (EC) was prepared and characterized as electrolytes for Li-ion batteries. Methods: In this work, we investigated four factors to demonstrate the performance of EMITFSI as electrolytes for Li-ion batteries. These factors include: thermal properties of mixed electrolytes (Mettler Toledo DSC1 Star -DSC, Q500-TGA), Conductivity (HP- AC impedance spectroscopy), Viscosity (Ostwald viscometer CANNON) and electrochemical window (cyclic voltammetry-MGP2 Biologic Instrument). All experiments were repeated three times with the exception of TGA-DSC methods. Results: The study indicated that 20 % wt. ethylene carbonate (EC) when mixed with EMITFSI could significantly decrease the electrolyte viscosity while improving ionic conductivity and maintain similar electrochemical stability as pure ionic liquid. Lithium diffusion coefficient of mixed electrolytes was lower than commercial electrolytes based on conventional solvents, however, the thermal stability was enhanced. Conclusion: EMITFSI can be used to replace conventional carbonate-based liquids as a high-performance electrolyte for Li-ion batteries.

This paper proposes a via array structure that is applicable to package in reducing radio frequency interference (RFI). The via array structure is applied to the redistribution layer (RDL) of the package for shielding purposes. To further validate the effect, the test structure is designed and fabricated using Yagi-Uda antenna and microstrip mitred bend (MMB) transmission line. The coupling between the transmission line and embedded antenna is investigated to determine the strongest noise coupling point, and via array structures are placed at those points. By applying the proposed via array structure, the measured coupling noise between the transmission line and the receiver antenna is reduced up to 12 dB.

These days smart devices are developing rapidly and becoming smaller. This recent trend requires the on-chip oscillator to be smaller and more accurate. A relaxation oscillator, which occupies a small area and consumes low power, is the potential candidate. However, its operation is sensitive to temperature and the supply voltage. Therefore, solution for these issues is very important. In this paper, we design a small area on-chip current-mode relaxation oscillator, that is insensitive to temperature and supply voltage variation, using voltage reference. The operation frequency of the proposed oscillator is 3.01MHz. And the frequency variation is 2.39% when supply voltage change from 1.4V to 2.0V and 1.09% when temperature change from -20°C to 100°C with the supply voltage of 1.8V. This oscillator is designed and fabricated in 0.18µm CMOS process, and the oscillator consumes 40µW and occupies 0.0196mm2.

Lithium-ion batteries (LIBs) have a profound impact on our modern society because of its diverse applications. In the state-of-the-art battery technology, the procedure for slurry preparation remains an important challenge which is vital for electrochemical performance enhancement and usually exhibits higher cost. In this work, two procedures are designated for the preparation of LiNi1/3Co1/3Mn1/3O2 (NMC111) cathode slurry. In procedure A, a mixture of active material and conductive carbons are blended with an additional NMP solvent, while, in procedure B, the NMP is introduced after mixing in dry of active material and carbons. Half-cell prepared by the method A exhibited better capacity and cyclability, which delivered 158.8 mAh g−1 and retained 89.8% capacity compared to 151.2 mAh g−1 and 81.3% obtained by the method B at 0.1 C rate. Full-cell also showed its superior performance with a maximum capacity of 155.5 mAh g−1 and 93.9% retention after 100 cycles. In the rate capability test, the cells fabricated by method A could perform well up to 2 C while, for method B, the cell shows poor performance. These outstanding performances were explained by the small charge transfer resistance of the cathode-based method A due to the well-dispersed electrode compositions.